3198: Add enable_write flag to FUSE and --enable-write and --read-only to

[arvados.git] / services / fuse / arvados_fuse / fusefile.py

diff --git a/services/fuse/arvados_fuse/fusefile.py b/services/fuse/arvados_fuse/fusefile.py
index fcb77116b84fc59fba6e6457778cfb3c9c155498..4d472cff1cca38380d80afa63b9783027ad1db30 100644 (file)
--- a/services/fuse/arvados_fuse/fusefile.py
+++ b/services/fuse/arvados_fuse/fusefile.py
@@ -1,6 +1,7 @@
 import logging
 import re
 import json
+import llfuse
 
 from fresh import FreshBase, convertTime
 
@@ -21,6 +22,9 @@ class File(FreshBase):
     def readfrom(self, off, size, num_retries=0):
         return ''
 
+    def writeto(self, off, size, num_retries=0):
+        raise Exception("Not writable")
+
     def mtime(self):
         return self._mtime
 
@@ -30,6 +34,10 @@ class File(FreshBase):
     def writable(self):
         return False
 
+    def flush(self):
+        pass
+
+
 class FuseArvadosFile(File):
     """Wraps a ArvadosFile."""
 
@@ -38,10 +46,16 @@ class FuseArvadosFile(File):
         self.arvfile = arvfile
 
     def size(self):
-        return self.arvfile.size()
+        with llfuse.lock_released:
+            return self.arvfile.size()
 
     def readfrom(self, off, size, num_retries=0):
-        return self.arvfile.readfrom(off, size, num_retries)
+        with llfuse.lock_released:
+            return self.arvfile.readfrom(off, size, num_retries, exact=True)
+
+    def writeto(self, off, buf, num_retries=0):
+        with llfuse.lock_released:
+            return self.arvfile.writeto(off, buf, num_retries)
 
     def stale(self):
         return False
@@ -49,6 +63,11 @@ class FuseArvadosFile(File):
     def writable(self):
         return self.arvfile.writable()
 
+    def flush(self):
+        with llfuse.lock_released:
+            if self.writable():
+                self.arvfile.parent.root_collection().save()
+
 
 class StringFile(File):
     """Wrap a simple string as a file"""
@@ -68,9 +87,15 @@ class ObjectFile(StringFile):
 
     def __init__(self, parent_inode, obj):
         super(ObjectFile, self).__init__(parent_inode, "", 0)
-        self.uuid = obj['uuid']
+        self.object_uuid = obj['uuid']
         self.update(obj)
 
-    def update(self, obj):
+    def uuid(self):
+        return self.object_uuid
+
+    def update(self, obj=None):
         self._mtime = convertTime(obj['modified_at']) if 'modified_at' in obj else 0
         self.contents = json.dumps(obj, indent=4, sort_keys=True) + "\n"
+
+    def persisted(self):
+        return True